const double FGJSBBase::inchtoft = 0.08333333;
const double FGJSBBase::Reng = 1716.0;
const double FGJSBBase::SHRatio = 1.40;
-const string FGJSBBase::needed_cfg_version = "1.55";
+const string FGJSBBase::needed_cfg_version = "1.57";
const string FGJSBBase::JSBSim_version = "0.9.1";
queue <FGJSBBase::Message*> FGJSBBase::Messages;